When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Mechanical Problems/Vehicle Issues and Fix-it ForumIf you've got a problem you just can't figure out, a noise you can't diagnose, or a Check Engine Light that won't go away, ask about it here!
Since I had bought the car (2003 Civic EX D17A2 standard trans) it’s had two codes being thrown. Code P0401 (not my main concern) and code P1259. My focus is on the P1259 code. I’ve read through the old threads and figured I’d try the easiest possibility (low oil level/pressure), I didn’t check oil pressure as I’m unsure on how to do so. I did perform an oil change and changed the filter while I was at it. I discovered it is leaking oil from the drain pan gasket (that stupid liquid gasket crap). I’ve yet to do the drain pan gasket to see if that’s the only place it’s leaking but I have a feeling it’s not the exact location of the leak. I’ve been keeping an eye on my oil level and it hardly shows it’s lost any. The car will still get thrown into limp mode (safe mode) and be reduced to maximum revs of 3800-3900RPM, I feel this is being caused mainly by code P1259 although I wouldn’t be surprised if both codes are to blame. When looking around on the block I notice areas of oil on the left side. I know you guys can only provide so much info without seeing it and I currently don’t have pics of the areas I’m talking about but I can try to upload some later today. Also i did see a thread about checking the continuity of the VTEC solenoid but that was like reading a foreign language.
Last edited by 03_EM2; Mar 21, 2018 at 06:57 AM.
Reason: Title change
If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
Posts: 32,017
Likes: 256
From: Midwest. Aiming about mid-chest
Rep Power: 518
Re: Need help with P1259 code
(that stupid liquid gasket crap)
This is the greatest stuff since sliced bread!
Has the engine been apart? Pan was taken off, installer borked the sealant?
Head off? Manifold off? (wrong intake gasket was used--that's a fairly common cause of EGR code)
P0401 is often caused by EGR passages clogging, remove intake manifold to scrape carbon buildup out of the EGR distribution plate. Lots of times this can cause mysterious misfire codes too, as buildup isn't equal to all cylinders
P1259 code is causing the low rev limit.
Got any freeze frame data to go with the code ?
these conditions must be met:
When the solenoid is off, the pressure switch must be on
When solenoid is turned on, pressure switch must turn off within 5 seconds
Failing to meet either condition will cause it to code.
A really good scanner can show these working in the live data lists.
Otherwise, I've rigged up meters and test lights to "watch" these in action as it happens, and/or control it manually
Also...PCM won't allow VTEC to operate unless it's in gear with wheels turning
Has the engine been apart? Pan was taken off, installer borked the sealant?
Head off? Manifold off? (wrong intake gasket was used--that's a fairly common cause of EGR code)
P0401 is often caused by EGR passages clogging, remove intake manifold to scrape carbon buildup out of the EGR distribution plate. Lots of times this can cause mysterious misfire codes too, as buildup isn't equal to all cylinders
P1259 code is causing the low rev limit.
Got any freeze frame data to go with the code ?
these conditions must be met:
When the solenoid is off, the pressure switch must be on
When solenoid is turned on, pressure switch must turn off within 5 seconds
Failing to meet either condition will cause it to code.
A really good scanner can show these working in the live data lists.
Otherwise, I've rigged up meters and test lights to "watch" these in action as it happens, and/or control it manually
Also...PCM won't allow VTEC to operate unless it's in gear with wheels turning
Unsure on what work has been done to the engine. My best guess is that someone just did a crappy job on the gasket.
The guy I bought it from said he had the head replaced along with water pump and timing.
I’m fairly up to speed on the P0401 code just haven’t taken the time to pull the manifold off yet.
Not much freeze frame data since the only form of a code scanner I have is a dinky little CarMD tool, but will upload a pic of what the scanner is showing once I’m off work.
Woudl my best bet be to buy a better scanner to monitor the activity between solenoid and pressure switch or is there a simpler option like the “rigged meters” you referred to. I’ve got a basic knowledge of electrical since it’s what I do for a living but when it comes to cars I’m not so knowledgeable but can manage with some guidance.
Really appreciation your feedback!
"Marge, anyone could miss Canada! All tucked away down there."
Joined: Feb 2016
Posts: 9,636
Likes: 1,283
From: Barrie, ON Canada
Rep Power: 222
Re: Need help with P1259 code
Possibly, I don't have vtec so I'm not sure. I'll check
Edit: I couldn't find anything for vtec/variable valve timing.
It may be in there but I couldn't find anything.
There may be a different app that does show it.
Last edited by Colin42; Mar 22, 2018 at 01:11 PM.
Reason: added info
If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
Posts: 32,017
Likes: 256
From: Midwest. Aiming about mid-chest
Rep Power: 518
Re: Need help with P1259 code
I’ve got a basic knowledge of electrical since it’s what I do for a living but when it comes to cars I’m not so knowledgeable but can manage with some guidance.
"Capable scanner" could be as simple and cheap as a pair of very low wattage 12v test light bulbs (#194 bulbs and some wire LOL)
find a wiring diagram for a VTEC system, it's pretty basic.
Solenoid receives 12v to operate when needed
Pressure switch is a simple 2 wire SPST that grounds the signal wire when it's on. (signal wire of course has a bias voltage applied to it by the PCM, other wire is a ground)
This can let you figure out if the system works or not, then you can try to figure out what is wrong after it codes
Hacked up head gasket jorb????
Pull the valve cover and look for this (hope the image embeds here)
"Capable scanner" could be as simple and cheap as a pair of very low wattage 12v test light bulbs (#194 bulbs and some wire LOL)
find a wiring diagram for a VTEC system, it's pretty basic.
Solenoid receives 12v to operate when needed
Pressure switch is a simple 2 wire SPST that grounds the signal wire when it's on. (signal wire of course has a bias voltage applied to it by the PCM, other wire is a ground)
This can let you figure out if the system works or not, then you can try to figure out what is wrong after it codes
Hacked up head gasket jorb????
Pull the valve cover and look for this (hope the image embeds here)
Thanks, I’ll work on rigging a tester up and finding the diagram. Are all the VTEC diagrams the same? Got plenty of test light bulbs at my shop. I noticed yesterday a smell of something burning/getting very hot, popped the hood and noticed a fair amount of oil on the front for the block, right where the engine code is stamped. It looks like it leaking fairly much. Asked my buddy what he thought he said it’s my main seal. Sadly I didn’t think to get pics at the time. Really starting to consider buying a back-up motor for when this one goes. Damn car has 273,000 on it..
Last edited by ezone; Mar 23, 2018 at 08:31 AM.
Reason: added missing quote bracket
Your main seal is about 6 inches below the stamped code on the block so while indeed that may be leaking, your also leaking somewhere else or your storing your car upside down..
Your main seal is about 6 inches below the stamped code on the block so while indeed that may be leaking, your also leaking somewhere else or your storing your car upside down..
Well no in fact it’s not stored upside down lol. He just gave it a quick glance and probably didn’t give it much thought (some friend huh). I’m going to check for that bolt to see if it’s missing if it’s not then I’ll start cleaning off the oil from everywhere I can and wait for a few hours or maybe a day to see if I can try to find the source of the leak. Starting to regret buying such a high mileage car.
"Marge, anyone could miss Canada! All tucked away down there."
Joined: Feb 2016
Posts: 9,636
Likes: 1,283
From: Barrie, ON Canada
Rep Power: 222
Re: Need help with P1259 code
Originally Posted by 03_EM2
Thanks, I’ll work on rigging a tester up and finding the diagram. Are all the VTEC diagrams the same? Got plenty of test light bulbs at my shop. I noticed yesterday a smell of something burning/getting very hot, popped the hood and noticed a fair amount of oil on the front for the block, right where the engine code is stamped. It looks like it leaking fairly much. Asked my buddy what he thought he said it’s my main seal. Sadly I didn’t think to get pics at the time. Really starting to consider buying a back-up motor for when this one goes. Damn car has 273,000 on it.. [/left]
That could be coming from the vtec solenoid, cam plug, or maybe the valve cover
If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
Posts: 32,017
Likes: 256
From: Midwest. Aiming about mid-chest
Rep Power: 518
Re: Need help with P1259 code
Asked my buddy what he thought he said it’s my main seal.
Um, no. Stop asking him questions LOL
Smell will likely be oil leaks + heat.. At that mileage every rubber gasket is suspect. Leak where you said should be valve cover gasket and/or cam plug (where a distributor would have been)
VTEC solenoid probably leaks too unless it was replaced in the last 100k miles, that would probably drip more down the back of the block than the front
VTEC are all similar in operation (maybe not wire colors) if you can read a diagram and understand how one would work electrically......they are all just a solenoid to open a hydraulic passage and a pressure switch to tell the computer the system did in fact open that passage and pressure did in fact reach its target
Smell will likely be oil leaks + heat.. At that mileage every rubber gasket is suspect. Leak where you said should be valve cover gasket and/or cam plug (where a distributor would have been)
VTEC solenoid probably leaks too unless it was replaced in the last 100k miles, that would probably drip more down the back of the block than the front
VTEC are all similar in operation (maybe not wire colors) if you can read a diagram and understand how one would work electrically......they are all just a solenoid to open a hydraulic passage and a pressure switch to tell the computer the system did in fact open that passage and pressure did in fact reach its target
Yeah...he’s no longer my “go-to” guy for mechanics after this lol just an assistant. I’ll go a new valve cover gasket. Since I don’t know much of the previous history on the car I’ll look around a few junkyards to find another vtec solenoid, assuming I should find one for a D17? I’ve really been procrastinating taking the pics but I’ll get my lazy butt out there right now to snap some to give you guys better understanding of what I’ve got goin on. I don’t have tool so I can’t remove the valve cover yet but that’ll come soon.
Here are the pics I gathered. Some might not show everything but it’s the best I could get without removing half the intake. Also I looked on the back of the solenoid a lil more and could see a drop of oil so I have some suspicion that it might be time for a new one.
Front of motor @ stamp Near the rear of block More rear of block More of stamp More of stamp Just noticed, could be nothing but it seems to me that there should be a bolt or something in there. I’m sure I could be wrong but couldnt hurt to know
If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
Posts: 32,017
Likes: 256
From: Midwest. Aiming about mid-chest
Rep Power: 518
Re: Need help with P1259 code
Gold painted valve cover + YUUUGE WADS of gray goo hanging out + blue gasket? Hack job! Installer was borked LOL (did you buy this from a kid?)
Cam plug leaks also end up running down the front of the bellhousing/block area
Ignore that bolt hole. Wasn't used in that car.
You took pics of where the leakage ends up.
Find where it begins!
(Much like finding a pond and wondering how it got there, never looking for the stream that feeds it)
Clean it all spotless so you can find fresh oil trails after a drive?
After seeing all the wads of goo someone made....now I kinda wonder if there might be wads of sealant caught in the VTEC filter screen.
Gold painted valve cover + YUUUGE WADS of gray goo hanging out + blue gasket? Hack job! Installer was borked LOL (did you buy this from a kid?)
Cam plug leaks also end up running down the front of the bellhousing/block area
Ignore that bolt hole. Wasn't used in that car.
You took pics of where the leakage ends up.
Find where it begins!
(Much like finding a pond and wondering how it got there, never looking for the stream that feeds it)
Clean it all spotless so you can find fresh oil trails after a drive?
After seeing all the wads of goo someone made....now I kinda wonder if there might be wads of sealant caught in the VTEC filter screen.
I got it from a guy that looked late 20s maybe mid 30s, his knowledge on what he was doing is a major question to me now, and considering he said he’d changed the water pump and timing. I’ll get half of the CAI off to have more room to look for the source of the rear leak. Sadly I can’t get the valve cover off until I get with my buddy and we run to his shop so I can have tools. Where would my cam plug be (other than near the cam lmao) not the most experienced myself but I don’t have the funds to send it to a shop for everything to be fixed yet so I’m trying to do the best I can with my limited skills.
Just to be clear, the amount of “leak” needed to fail the vtec system would leak your engine dry in moments.
Agree way too much RTV was used in putting the valve cover back on, before removing I would suggest having a new gasket on hand. Always easier to return a unopened part than trying to run out and get one.
While there is no way excess rtv on the valve cover could get into the vtec due to the pickup screen and oil filter, who knows what he did if he reinstalled the selenoid for some reason.
start with testing, no reason to replace a good selenoid if it’s a bad pressure switch or wire..
